Due to many excellent performance characteristics, such as thin body and low power consumption, LCDs are extensively used in a variety of electronic devices. Generally, most of LCDs are back-light type. The LCD includes a LCD panel and a backlight module. Liquid crystal molecules are set between two glass substrates, and change their directions by means of controlling the glass substrates to be charged or not. The LCD panel refracts light emitting from the backlight module to show an image.
Liquid crystal photo-alignment technology is very important for manufacturing LCD panel. The image quality of the LCD is associated with the quality of the liquid crystal photo-alignment. The LCD shows a high quality image only if the liquid crystal molecules in LCD panel are arranged stable and uniform. Generally, an alignment film is used to make directional alignment of the liquid crystal molecules, and a liquid crystal photo-alignment device is used in the liquid crystal photo-alignment technology. In particular, when the glass substrate is applied to a voltage, a LC pretilt angle is formed on a surface of the alignment film in a manner that ultraviolet radiation impinges on the monomer in the liquid crystal molecules to make their reaction to form fit, thereby achieving the function of liquid crystal photo-alignment. In order to accelerate the reaction, a platform of the liquid crystal photo-alignment device, which is configured for supporting the glass substrates, needs to be heated to a certain temperature, average of 40˜50° C. In order to form a certain alignment angle under the ultraviolet radiation, the entire supporting surface of the platform must keep the same temperature, and error needs to be controlled within ±3°. However, particles in air, abrasion debris, or other foreign objects are easily fallen on the platform when placing the glass substrates on the platform. If the dimension of the foreign objects is larger than 1 mm*1 mm, the temperature of the area having the foreign objects will be very different from that of the other area of the platform. Furthermore, the foreign objects can influence the reflection and refraction of the ultraviolet radiation, and cause an abnormal photo-alignment of the area having the foreign objects. This decreases the product yield. Thus, the platform needs operators to do regularly manual cleaning.
Therefore, it is desired to provide a liquid crystal photo-alignment device, which can overcome or at least alleviate the above-mentioned problem.